Every Highway Has Its Limits Engineers Recommend 6 Speed Zones For Interstate 90

If the Idaho Transportation Board follows the advice of highway engineers, Interstate 90 through the Idaho Panhandle soon will have six different speed zones.

From the Washington to the Montana border, drivers would pass consecutively through 70, 65, 75, 65, 60 and 55 mph speed zones.

Confused? North Idaho police are afraid you will be.

Highway engineers say they merely want the limits to reflect the speeds people already are driving.

And “if we want faster speeds on open stretches of road, then we’re going to have to live with speed changes,” said John McHugh of Coeur d’Alene, a member of the Transportation Board.

The board will begin hearing recommendations today on what speed limits to place on various sections of Idaho highways.

Earlier this year, the Idaho Legislature changed the maximum speed limit on interstates from 65 to 75 mph. It also raised the maximum speed on state highways from 55 to 65 mph.

Idaho Transportation Department engineers have been studying Idaho’s 5,000-mile highway system since February, looking at what speed limits would be safe.

Transportation Board members will meet with department officials today in Lewiston to hear their recommendations. However, they will discuss only some of the highways.

The department will present its recommendations on 570 miles of interstates and about 614 miles of other state and U.S. highways today, said Jeff Stratten, department spokesman.

Department engineers are continuing to study other portions of the highway system and plan to finish making their recommendations by June, Stratten said.

I-90 is the only highway in North Idaho that is scheduled to be discussed today. It runs about 73 miles across the Panhandle.

The Transportation Department will recommend raising the speed limit on two portions of the interstate - to 70 and 75 mph - and leaving the rest the same.

“I’m sure it’s going to cause a lot of confusion,” said Nelson Morris, chief deputy for the Shoshone County Sheriff’s Department.

Idaho State Police agree.

“It will be confusing for motorists to travel through that many speed zones for such a short distance,” said Lt. Doug Camster. ISP had recommended a more consistent speed limit to the ITD, he said.

“It will make it more difficult to enforce because it will be confusing,” Camster said. “However, we will support whatever the governor elects to implement and enforce it appropriately.”

The department knew there might be confusion because of the halfdozen speed zones, said Jim Armitage, ITD district traffic superintendent in Coeur d’Alene.

But engineers based their recommendations primarily on how fast drivers already were going through a measurement called the 85th percentile, he said.

Their studies showed that from the Washington border to Coeur d’Alene, 85 percent of drivers were traveling at just over 70 mph or below. From Rose Lake to Osburn, 85 percent of drivers were traveling about 74 mph, Armitage said.

Engineers also decided to recommend that the Washington-to-Coeur d’Alene speed rise only to 70 because Washington’s limit is at 70 mph. Traffic on that portion of the highway also is more congested, Armitage said.

“I don’t see problems with those recommendations personally,” said board member McHugh.

McHugh said he expects the board to begin voting on whether or not to change the speed limits today.

The Transportation Board is made up of six voting members and a chairman who votes only in a tie.

However, any decision made by the board would not go into effect until May 1 and even then, not until the speed limit signs have been changed.

The Transportation Department estimates the 264 interstate speed signs could be changed in three to five days.

On non-interstate routes, raising speed limits will involve more than just sign changes and will take longer.

“Two-lane highways with passing and no passing zones, for instance, would need to be re-striped to reflect shorter passing distances when driven at a higher speed,” Stratten said.

, DataTimes ILLUSTRATION: Color photo

MEMO: This sidebar appeared with the story: PROPOSED CHANGES Interstate 90 speed limits from the Washington-Idaho border to Montana: 70 mph: From the Washington border to Coeur d’Alene 65 mph: From Coeur d’Alene to the Rose Lake junction 75 mph: From the Rose Lake junction through the Silver Valley to Osburn 65 mph: From Osburn to Wallace 60 mph: From Wallace to Mullan 55 mph: From Mullan to the Montana border